Malaria remains one of the world's gravest medical threats. According to the World Health Organization, the disease kills more than a million people each year, and there are another 300 million acute cases, mainly in sub-Saharan Africa. Most of the dead are young children.

The newest malaria drugs are a lot more expensive than older treatments, but as VOA's Art Chimes reports, new research indicates cheaper treatments may be just as effective in treating the disease and preventing re-infection.

Malaria is caused by a parasite spread by mosquitoes. For years, the standard treatment was chloroquine, but the parasite has developed resistance to the drug, and it is no longer very effective.

The World Health Organization generally now recommends treatment based on artemisin, one of the newest anti-malarial drugs. Administered with other medicines in what is called ACT, or Artemisinin Combination Therapy, the treatment is effective, but expensive.

Now, new research indicates that some older, cheaper medicines may work just as well. "In summary we found that the other inexpensive regimen, amodiaquine plus SP, performed at least as well as the more expensive ACT regimen, and actually performed somewhat better at two of the sites," said Dr. Phil Rosenthal of the University of California - San Francisco. In studies involving more than 2,000 patients in Uganda, Dr. Rosenthal said it's not that artemisinin-based ACT treatment didn't work, "it's that amodiaquine SP -- the non-ACT regimen -- performed very well."

The good results from the amodiaquine-SP combination in this study are explained in part by how the researchers measured success. Because malaria re-infection is so common, they looked at the success of a treatment in keeping the patient malaria-free, not just in curing the original infection.

"And it so happens that [the] non-ACT regimen that we studied, amodiaquine plus SP, has a better effect at preventing a second infection because the drugs are rather long-acting. They stay in your bloodstream for a long time after treatment," noted Dr. Rosenthal.

The third treatment they studied - chloroquine - was the drug of choice for many years, but Phil Rosenthal says the malaria parasite has developed resistance to it. Nevertheless, it is still in use because it's so cheap. "Most people are still being treated with chloroquine, which is really a horrible situation. Chloroquine is probably very close to placebo in most of Africa. That is clearly sub-optimal, that we're relying on such a poorly effective drug."

There has been resistance to using artemisinin-based therapy because of the cost. But the amodiaquine - SP combination, which the researchers found can provide a similar level of protection, is a lot cheaper. Somewhat more expensive than chloroquine, to be sure, but about 75% less than the artemisinin-based ACTs.

Findings of the study on malaria treatments in Uganda, which was led by Phil Rosenthal's colleague Grant Dorsey, are published in the open access journal PLoS Medicine. 'Open access' means the articles are free to read. The high cost of subscriptions to some biomedical journals has become an issue, and in an e-mail from Uganda, Dr. Dorsey wrote that "it is frustrating that people from resource-poor settings may not have access to up-to-date medical literature without paying expensive subscription fees." And he says he is "frequently approached by African scientists trying to gain access to full text articles," but they can't read about the latest research unless they pay for it.